Because you have only 1GB RAM, I would discourage running a 3D desktop shell such as Unity (3D) or Gnome Shell. If you feel that Unity 2D is too slow or you simply don't like the interface, fear not! You still have other options such as Xfce and LXDE (easiest way to use them are by downloading Xubuntu or Lubuntu). Considering your machine has its age, you shouldn't have any driver issues with an existing release so there's no need to jump the gun on Ubuntu 12.04, I strongly recommend waiting for its release. Feel free to try live CD's of Ubuntu, Xubuntu and Lubuntu 11.10, you can even mess around with them, install them to your system (make sure you have your files backed up), that way when Ubuntu 12.04 comes out, you'll most likely already know which desktop environment you'll want to use.

Xfce and LXDE in their most recent versions have eject buttons for removable media in their file managers, I'd say they're very user-friendly. Xfce even supports editing the applications menu graphically. Personally I'd much rather run Xfce or LXDE on such a machine than Unity 2D, and spare the RAM for apps that matter, such as Firefox, LibreOffice and GIMP.

"only 1GB RAM"? I have been thinking about putting ubuntu to a REALLY old machine, with only 640MB RAM. Maybe I should leave it as Fedora 6 (yeah, really old one), don't even bother with ubuntu. I don't run much on that, just as a file server and a very light web server.
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G. HeApr 4 '12 at 1:46

With 640MB RAM you'll be flying with Xfce or LXDE. I've found Xfce gets crippled if you have less than 512MB RAM, and LXDE gets crippled if you have less than 256MB RAM. The desktop environment has a greater impact than the distro you use IMHO.
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titaniumtuxApr 4 '12 at 5:57

There is a particular problem with Ubuntu 12.04's installer and some older Athlon CPUs, including the 2200+. The installer will crash at an early stage unless you run a workaround. Fortunately the workaround is pretty simple.

When you boot the Ubuntu 12.04 live CD (or USB), choose 'Try Ubuntu before you install'. It will (eventually!) boot into the Ubuntu desktop. Click on the Ubuntu icon (top left) and type 'terminal'. Click the Terminal icon that comes up. In the terminal, type:

sudo apt-get remove ubiquity-slideshow-ubuntu

and press enter. This will remove the package that causes the problem. You can then double-click on the 'Install Ubuntu 12.04 LTS' icon and you should be fine.

I should add, though, that there is another unfortunate bug associated with this range of old Athlon CPUs, and that is that Adobe's latest version of Flash for Linux at the time of writing, 11.2, is compiled in such a way that it no longer runs on these chips. I read that it is possible to install an older version (11.1 is said to work). It's a kludge, but one I am prepared to try!

That should not be a problem at all. Indeed, I would expect 12.04 to run quite a bit faster on that hardware than 11.10 did. The one question is graphics. I don't think your VGA is supported by AMD, so you probably won't be able to use their proprietary driver, but I think the open radeon driver should work. It is likely that you won't be able to use the default Unity shell (Compiz-based), but Unity 2D should work well since it uses Metacity. And of course, Ubuntu has many other shells available as well.

I can't see any reason why you shouldn't be able to get many more years out of that box.

Yeah,AMD droped a support long time ago.But i have a X11.conf that i have created earlyer for an older version of ubuntu and it's working just great,i can't use some apps like blender and stuff but the most are working just great.Thanks for your answer.
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NightwalkerkgApr 1 '12 at 11:34